HE is America's best-known left-wing agitator and for years his love of country has been under question, with the Bush administration and its supporters leading the charge.

But now documentary filmmaker Michael Moore says he has joined the mainstream and will no longer tolerate people branding him anti-American.

"Don't ever question my patriotism," a clean-shaven, besuited Moore bellowed at a questioner at New York's plush Regency Hotel on Park Avenue yesterday where he was promoting Sicko, a new documentary that tears the scab off the profit-driven US health system.

"I am a patriotic American. The most patriotic thing you can do is question your government, especially when they're screwing up like they are by not providing healthcare to our 9/11 rescue workers."

There was even a new, star-spangled element to Moore's trademark condemnation of President George W. Bush and the war in Iraq.